Apparatus for bulking yarn



y 1951 c. J. GONSALVES 2,982,000

APPARATUS FOR BULKING YARN Filed July 19, 1956 2 Sheets-Sheet 1 INVENTOR ATTORNEY y 1961' c. J. GONSALVES 2,982,000

APPARATUS FOR BULKING YARN Filed July 19, 1956 2 Sheets-Sheet 2 INVENTOR 621mm Jwe w 6011501005 ATTORNEY APPARATUS FOR BULKING YARN Conrad Joseph Gonsalves, Arnhem, Netherlands, assignor, by mesne assignments, to E. I. du Pont de Nemours and Company, Wilmington, DeL, a corporation of Delaware Filed July 19, 1956, Ser. 510. 598,842

4 Claims. 01. 28-1 This invention relates to the manufacture of bulked yarn and is more particularly concerned with an apparatus for the continuous bulking or fiuffing of multi-filament yarn to produce a textile product characterized by a large number of individually curled filaments.

It is known to produce synthetic continuous filament yarn having a fluffy appearance by subjecting succeeding lengths of a parallel filament yarn to an air blast and then, by some means, locking the curl and fiuif in position. There are a good many types of apparatus which will produce satisfactory results in the manufacture of curled yarn, but the art continues to seek easier and more reliable operation and the production of fluffiness that is better controlled and is more uniform through the long lengths of bulked yarn.

It is an object of the present invention to provide a method and apparatus for bulking yarn whereby an increased curling efiect is achieved; the yarn produced according to the present invention being characterized by good handle, good knitting and weaving properties and excellent over-all appearance.

It is a further advantage of the present invention that the amount of compressed air used to bulk a given length of yarn is somewhat reduced as compared to prior art requirements.

Other objects and advantages of this invention will be apparent upon consideration of the following detailed description of several embodiments thereof in connection with the annexed drawings, wherein:

Figure 1 is a view in vertical section of an air jet constructed in accordance with the principles of the present invention;

Figure 2 is an end elevation of the bushing of the Figure 1 assembly through which air streams are supplied to the yarn or thread path;

Figure 3 is a view similar to Figure 1, but showing a different type of air supply bushing; and

Figure 4 is a view in end elevation of the air supply bushing of the assembly of Figure 3.

Referring now to Figures 1 and 2 in greater detail, the numeral 10 represents a body from which the entire air jet is supported. In this regard, note that the body 10 is provided with a flange 11 having therein bolt holes at 12. The body 10 has coaxial bores therein of three different diameters. At the upper end, it is provided with an internally threaded bore 13 and, at the lower end, there is an internally threaded bore 14 of larger diameter than the bore 13. In between the bores 13 and 14, there is a cavity or bore 15, greater in diameter than the bore 13 but smaller than the bore 14. Threaded into the bore 14 is a somewhat elongated externally threaded nipple 16 having a frusto-conical concave upper surface. The nipple 16 is provided with a central, axial passageway at 18 through which the yarn emerges to impinge upon a baffle 19 disposed adjacent to the mouth 20 of the nipple 16 as can be seen in the drawing. The flufied and curled yarn is withdrawn from the baflie 19 over a guide 21 to a collecting device not shown.

In the upper bore 13 of the body 10 there is located a nozzle 22 having an externally threaded portion and a central axial bore at 23. The nozzle 22 is held in position of adjustment by a lock nut 24. The lower end of the nozzle 22 terminates in a frusto-conical tip 25 and within the tip there is an axial continuation of the bore 23 forming an orifice 26. The orifice 26, however, is of smaller diameter than the bore 23. When the nozzle 22v and the nipple 16 are in position, it can be seen that the cavity at 15 coaxially surrounds the nozzle .22, the bottom of the cavity being defined by the inverted frusto-conical base of the nipple 16.

The cavity at 15 in the body 10 is provided with a radial access channel at 27 to which air is supplied through a fitting at 28. A bushing 29 having a conical lower'surface surrounds the lower end of the nozzle 22 and rests on the upper conical surface of nipple 16. This bushing is held in position with respect to tip 25 and nipple 16 by a coil spring 30 coaxially surrounding a portion of thenozzle 22. The bushing 29 has axial ports extending therethrough so that air maybe supplied from a source, not shown, through the fitting 28, channel 27, cavity 15 and thence through the ports in the bushing 29 to lateral contact with the yarn. An important part of the present invention resides in the aperturing of the bushing 29 and so that this may be easily understood, a bottom plan view of that bushing appears in Figure 2. The bushing has a central aperture in which the tip 25 of the nozzle 22 lies, the nozzle mouth being countersunk from the lower end of the nozzle tip to a small extent. The bushing is provided with two cut out channels at 31 and 32; these channels defining with the adjacent walls of the cavity 15 a pair of air passageways parallel to the central passage 23 in the nozzle 22. At the bottom of the two passages 31 and 32 they connect with two sloping lateral passages 33 and 34 which extend to a position immediately adjacent the outlet end of the nozzle 25. In view of the tangential disposition of the pasageways 33 and 34 in relation to the orifice 26, a swirling action of the air in relation to the thread is produced. The air has a component of motion tangential or chordwise of the yarn passageway 23-2618, as can be seen from Figure 2 and a component axially of the yarn path as can be seen in Figure 1. While the swirling action is desirable in any event, it has been found that it is particularly good when the air swirl has the same direction as the twist which is in the thread before it enters the air jet.

It has been found as a part of this invention, that the location of the outlet of the channels 33 and 34 in relation to the outlet of the orifice 26 in the nozzle tip 25 is very important. It can be seen that the spring 30 will hold the bushing 29 in position and by loosening the nut 24, the nozzle 22 can be freed for vertical adjustment to a critical extent by screwing it up or down in the threaded bore 13 as may be necessary. It is then locked in the desired position of adjustment by tightening the nut 24.

The form of air jet shown in Figure 3 differs from that shown in Figure 1 in-the shape of the bushing and in the manner of locating it within the cavity. Parts which correspond to those shown in Figure I bear like numbers. Different parts are differently numbered. The bushing of Figure 3 bears reference numeral 35 and is pressed against the upper surface of nipple 16 by a sleeve 36 which is both internally and externally threaded. The external threads of the sleeve 36 mesh with the threads of the bore 13 and the internal threads receive an externally threaded nozzle 37 which passes centrally through the bushing 35 and terminates in a sleeve 38. Thus, the bushing 35 is held in position by the sleeve 36. By this arrangement, the spring 30 of Figure 1 is rendered unnecessary. The nozzle 37 is adjusted axially by rotating it about its threads within the sleeve 36 and is held in Patented May 2,1961

adjusted position by lock nut 39. For the purpose of this adjustment, the nozzle is provided with a wrenchreceiving flange at 40. The bushing 35, unlike the bushing 29, is provided with four axially extending air passageways, bearing numerals 41, 42, 43 and 44. At the base of these air passageways, there are four ports 45, 46, 47 and 48 respectively. These ports terminate, as can be seen in Figure 4, in a swirling chamber 49 constituting a part of the bushing 35. The tube 38 projects slightly into this chamber 49. The nipple 16, the body portion 10, the air fitting 28, as well as the bafile 19, correspond in structure and function to the apparatus already described in conjunction with Figures 1 and 2.

It will be noted that the ports or passageways 45, 46, 47 and 48 are equally circumferentially spaced as are the channels 33 and 34 of Figures land 2. The ports 45 to 48 inclusive, slope inwardly in the direction of yarn travel and they project an air stream tangentially or chordwise across the yarn passageway as viewed in Figure 4. At the plane of view of Figure 4, the yarn passageway is defined by the tube 38. The swirling air stream may advantageously circulate in the same direction as the twist in the yarn being treated.

The bushings 29 and 35 are not full equivalents. The arrangement of Figure 2, while it produces satisfactory bulked yarn, tends to consume more air for bulking a given quantity of yarn than is the case with the bushing of Figure 4. When the relatively high consumption of air of the Figure 2 arrangement was observed, it was thought that precision machining of the channels would help. It has been found, however, that punching the orifices as in the case of Figure 4, within very close tolerances, i.e., within a few microns, will improve the consumption of air. The diameter of the punchings 45, 46, 47 and 48 is 0.5 mm. The orifices slope parallel to the frusto-conical base of the bushing and they are arranged as can be seen in the drawing.

What is claimed is:

1. An air jet for bulking twisted yarn comprising a nozzle, means defining coaxial yarn passageways leading to and from said nozzle, the means defining the passageway leading from the nozzle being a longitudinal bore within a nipple having a conical entrance surface close to the exit end of the said nozzle, a bushing coaxially surrounding said nozzle and having channels therein sloping inwardly in the direction of yarn travel and discharging adjacent the nozzle tip in a direction generally chordwise of the yarn path and in the same direction as the twist in the said yarn, means including an air supply to said bushing for whipping the yarn about and forming curls therein, means to adjust the relative axial position of the nozzle tip and the bushing, and means positioned at the exit end of the passageway to change the direction of yarn travel abruptly.

2. An air jet as claimed in claim 1, in which the channels are two, which are equally circumferentially spaced.

3. An air jet as claimed in claim 1, in which the channels are four, which are equally circumferentially spaced and which are punched to a diameter of 0.5 mm. and to a tolerance of not more than about a few microns.

4. The air jet as claimed in claim 1 in which the said bushing is held in position by a spring.

References Cited in the file of this patent UNITED STATES PATENTS 984,195 Cooper Feb. 14, 1911 2,100,588 Claus Nov. 30, 1937 2,173,789 Nikles et al. Sept. 19, 1939 2,451,504 Mayo Oct. 19, 1948 2,515,299 Foster July 18, 1950 2,526,775 Slayter Oct. 24, 1950 2,639,487 Kelley May 26, 1953 2,667,964 Miller Feb. 2, 1954 2,852,906 Breen Sept. 23, 1958 2,869,967 Breen Jan. 20, 1959 FOREIGN PATENTS 161,076 Australia Dec. 24, 1953 520,934 Belgium Dec. 24, 1953 

